tools/virtio: 64 bit features

Missed one place where vringh_test used
long to pass features. Fix it up to u64.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

tools/virtio/vringh_test.c

@@ -132,7 +132,7 @@ static inline int vringh_get_head(struct vringh *vrh, u16 *head)
 	return 1;
 }
 
-static int parallel_test(unsigned long features,
+static int parallel_test(u64 features,
 			 bool (*getrange)(struct vringh *vrh,
 					  u64 addr, struct vringh_range *r),
 			 bool fast_vringh)